Whistle Pongbat

Peter Capraro

Michael Hankin

Anand Rajeswaran

Concept

• “Mortal Pongbat” meets “Brick”

• Paddle Control Options– Noise Controlled Paddle– Frequency Controlled Paddle

• Slide Whistle for more consistent sine waves

• Slide Whistle/Microphone Controller

Rules

• User scores if ball gets to right side of screen– Computer “blocks” protect that side

– Bullet system to destroy blocks

• “Computer” scores if ball gets to left side of screen– User has the paddle to protect this side

– Paddle gradient to alter direction of ball movement

• Game played to 5 points

Architecture

Audio Controller

• Uses CODEC for analog to digital conversion

• Splits clock to package sound byte WAV format (taken from MindTunes group, 2008)

• Passes 16 binary bits as converted integer

VGA Controller

• Component attributes passed from software– Paddle– Ball– Score– Blocks– Bullet

Address Data0x00 Paddle Height0x01 Ball X Coordinate0x02 Ball Y Coordinate0x03 User Score0x04 Computer Score0x05 Block 1 (Top Block)0x06 Block 20x07 Block 30x08 Block 40x09 Block 50x0A Block 6 (Bottom Block)0x0B Bullet Indicator0x0C Bullet Charging Counter0x0D Bullet X coordinate0x0E Bullet Y coordinate

Software• Paddle Control

– Integer representation of WAV format• Positive Numbers: 0 - 32,767

• Negative Numbers: 65,536 - 32,768

• Bullet Control– Three hits to charge

– One more hit fires

– Destroys one or two blocks

• Ball Control– Motion

– Direction

Frequency Algorithm• Tested In MatLab

– Slide whistle showed decent sine wave

– Broke down at extreme frequencies

• Algorithm– Essentially reduce to square

wave

– Average consecutive period measurements

• Frequency still inconsistent when frequency moved quickly– Solution: Tell user to move it

slowly

Paddle Movement Mechanism

• Problem– On average, calculated pitch followed expected

pitch– Wide and Constant Oscillation

• Solution– Extreme High and Low boundary values

required to change direction– Reaching boundary just once begins consistent

motion

Lessons Learned

• FPGA Board and hardware/software communication

• The importance of setting clear, simple, and testable goals

• Don’t reinvent the wheel…but don’t trust that it turns correctly in the first place.

• Not easy to work when somebody is always whistling annoyingly in the lab.